New England Distribution

Non-native: introduced
(intentionally or
unintentionally); has become naturalized.

County documented: documented
to exist in the county by
evidence (herbarium specimen, photograph). Also covers
those considered historical (not seen in 20 years).

State documented: never been
documented from the
county, but known from the state. May be present. Or,
may be restricted to a small area or a habitat (alpine,
marsh, etc.), so unlikely found in some
counties.

Note: when native and non-native
populations both exist in a county, only native status
is shown on the map.

North America Distribution

Facts About

Common interrupted-clubmoss is so called because each year's growth is noted by an interruption or constriction on the stem. It is also sometimes called bristly clubmoss because it is prickly to the touch.

Habitat

Alpine or subalpine zones, forest edges, forests

Characteristics

Habitat

terrestrial

New England state

Connecticut

Maine

Massachusetts

New Hampshire

Rhode Island

Vermont

Leaf shape

the vegetative leaves are short and scale-like

Spore leaf arrangement

the sporophylls are located on spore cones at the tips of the shoots or branches

Form of shoot

the plant has an upright stem, and the stem has simple branches

Horizontal stem

the horizontal stem is on the surface of the ground

Leaf differences

the vegetative leaves within a node are all similar in size and shape

Teeth on leaf edges

the edges of the vegetative leaves have tiny teeth

Spore leaf length

3–4.4 mm

Leaf outline

the vegetative leaves are widest above the base, then taper narrowly towards the tip (lanceolate)

the vegetative leaves are long and very narrow (linear)

the vegetative leaves are widest near the tip, but otherwise narrow and tapering (oblanceolate)

plants with specialized branches that produce gemmae and lacking spore cones, the spore-bearing leaves in alternating zones with the vegetative leaves (vs. S. annotinum, with plants lacking specialized branches that produce gemmae, and with spore cones at the apex of branches on mature plants).

1×2.
Spinulum annotinum
×
Spinulum canadense
→ This uncommon interrupted-clubmoss hybrid is located most frequently where the parent species are sympatric (e.g., on the higher mountains of
ME and
NH). It can be recognized by intermediate leaf length and dentition between the parental clones and shows 1–15 stomates per
½ adaxial surface on trophophylls from the middle of seasonal growth (compared with 25–53 per
½ adaxial surface in
Spinulum canadense).